Lupus anticoagulant in human immunodeficiency virus -infected patients on highly active antiretroviral therapy.

BACKGROUND: Lupus anticoagulant (LA) is a heterogeneous group of antibodies that causes a variety of clinical and laboratory effects; has been described in infections such as human immunodeficiency virus. LA has not been previously described in Nigerians with human immunodeficiency virus infection on highly active antiretroviral therapy (HAART). AIM: To determine the frequency of LA in patients infected with the human immunodeficiency virus on HAART. METHODS: Cross sectional study of patients with human immunodeficiency virus infection undergoing HAART at a tertiary hospital in Nigeria. Screening for LA was done using the activated partial thromboplastin time (aPTT) and kaolin clotting time (KCT). Mixing experiments were conducted on samples with prolonged clotting time. KCT ratio was calculated. A positive result was taken as KCT ratio greater than or equal to 1.2. Fisher's exact test was used to test the association between LA and sex. Association between aPTT and KCT was tested according to Pearson. P-value < 0.05 was considered significant. RESULTS: Fifty-eight patients aged 18- 60 years were studied, comprising of 28 males (mean age 40.50 plus/minus 8.8 years) and 30 females (mean age 35.4 plus/minus 9.02). Frequency of LA among human immunodeficiency infected patients was 5.2%, (frequency in males and females were 3.6 and 6.7 % respectively). This was lower than 46% reported in patients not on HAART. There was no statistically significant difference in LA prevalence between males and females P greater than0.05. A positive correlation was observed between the clotting tests aPTT and KCT (r is equal to 0.9406, p less than 0.0001). CONCLUSION: HAART may prevent development of LA in HIV-infected patients.

Lupus anticoagulant and leg ulcers in sickle cell anemia.

BACKGROUND: The cause of chronic leg ulcer (CLU) in patients with sickle cell anemia (SCA) is unknown; it has been attributed to hypercoagulability associated with the disease. Recently, it has been suggested that a subset of SCA patients may be prone to developing CLU and that hemolysis may be an underlying factor in the development of CLU. The lupus anticoagulant (LA) is an antiphospholipid antibody (aPLa), these antibodies have been described in patients with SCA. AIMS: This study was designed to determine the frequency of LA in SCA patients with CLU compared with those without CLU. MATERIALS AND METHODS: Study design is a descriptive, cross-sectional one. Thirty-three SCA patients with CLU and 33 patients without CLU were screened for the presence of LA using the Kaolin clotting time (KCT), which is an important assay, and Kaolin clotting time index was calculated. Means were compared using the students' t test, proportions were compared using the chi-square test, level of significance was set at 0.05, odds ratio was calculated. RESULTS: About 18.18% of patients with CLU had LA, compared with 6.06% among controls (P < 0.05); odds ratio was 3.44 (95% CI 0.64 - 18.51). CONCLUSIONS: We conclude that SCA patients with CLU may be more likely to develop LA, and this may be related to the degree of hemolysis. Further studies are required to find out if CLU and LA are a result of hemolysis or if LA is responsible for the higher incidence of hemolysis and CLU found among these patients.

Presence of lupus anticoagulant in an asymptomatic Nigerian.

BACKGROUND: The lupus anticoagulant (LA) is one of the antiphospholipid antibodies (aPL), which prolong phospholipid- dependent coagulation tests by interfering with coagulation reactions that depend on protein - phospholipid complexes in vitro. METHOD: A 25 year old 'healthy' male Nigerian was screened for the presence of any coagulation abnormality using the KCT, PT and platelet count; after volunteering for his plasma to be used in the preparation of normal pooled plasma in a study. RESULTS: He was discovered to have a prolonged KCT, PT and normal platelet count. Based on the prolonged KCT his plasma was subjected to mixing studies with various concentration of normal pooled plasma; the KCT index was calculated and a curve was plotted. His KCT index was 1.6 and the curve convex in the left axis suggesting the presence of LA. His past medical history and physical examination were not remarkable. Three months after the initial study, a repeat KCT index was 1.4 and the subject asymptomatic. CONCLUSION: From literature review this is the first report of LA in an asymptomatic adult Nigerian; the importance of this finding is discussed.

Presence of Lupus anticoagulant in an asymptomatic Nigerian

Background:The lupus anticoagulant (LA) is one of the antiphospholipid antibodies (aPL); which prolong phospholipid- dependent coagulation tests by interfering with coagulation reactions that depend on protein - phospholipid complexes in vitro. Method: A 25 year old 'healthy' male Nigerian was screened for the presence of any coagulation abnormality using the KCT; PT and platelet count; after volunteering for his plasma to be used in the preparation of normal pooled plasma in a study. Results: He was disco- vered to have a prolonged KCT; PT and normal platelet count. Based on the prolonged KCT his plasma was subjected to mixing studies with various concentration of normal pooled plasma; the KCT index was calculated and a curve was plotted. His KCT index was 1.6 and the curve convex in the left axis suggesting the presence of LA. His past medical history and physical examination were not remarkable.Three months after the initial study; a repeat KCT index was 1.4 and the subject asymptomatic. Conclusion: From literature review this is the first report of LA in an asymptomatic adult Nigerian; the importance of this finding is discussed